Finalize 3.3v MCU power regulator coupling capacitors

[bblacey]

Ensure 3.3v coupling capacitor capacity is sufficient to handle MCU, flash, ASTHA crypto chip and radio power surge demands.

[bblacey]

LDO will oscillate and won't settle unless capacitors are of sufficient capacitance. Ceramic and Tantalum capacitance differ in an important manner for the input side (RMS or EMF which is a secondary value but also important). Arduino tends to use 47uf on the input side. Consider through-hole tantalum on input side to keep costs lower. Place larger capacitance closer to LDO on output side.